Back Ports not working

I wanted to upgrade the PSU and vga card of my Hp pavilion slimline s5753w, but since the slimline is so small, barely anything would fit in it. I decided to put everything into an old Dell case i found layin around, and although some things are in some funky places, i got everything in and put in a Sapphire HD 5670 vga card, and a coolmax CA-400 400W ATX v2.01 PSU. Everything seems to be in place and everything turns on, but none of the back ports work. The monitor ports in the vga card, the monitor ports in the motherboard, the usb ports, the ethernet port, none of them work! Where have i gone wrong?

Computer specs:http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?lang=en&cc=us&objectID=c02776817&jumpid=reg_R1002_USEN
PSU - http://www.newegg.com/Product/Product.aspx?Item=N82E16817159043&Tpk=COOLMAX%20CA-400%20400W%20ATX%20v2.01%20Power%20Supply

VGA Card - http://www.newegg.com/Product/Product.aspx?Item=N82E16814102930

Additional Note: I may have inserted the PCI-E VGA card without disabling the integrated graphics. Could this be the problem? Also, I can't get any monitor on so i won't be able to turn this off now.

 

Maybe someone else with a bit more knowledge here could help better. (This is just me thinking) But if you remove your Graphics card and re-boot could you access your monitor?
Also was your Graphics Card compatible with your system?

 

Two thoughts! BIOS setting or board drivers.

 

Yes, I've tried removing my vga card and rebooting, and i've also tried going back to my 220W stock PSU (without the vga card in) and neither worked. Just tried resetting the Bios, and got nothin'. And board drivers is something i need to download correct? How could I download it if i can't get my monitor to get a signal :l.